Objective:To investigate the effects of anti brain-derived neurotrophic factor (BDNF) high affinity receptor tyrosine kinase B (TrkB) antibodies on nitric oxide(NO) concentration in rat hippocampus after forebrains ischemia. Methods:Hippocampal NO concentration was measured directly by an NO-selective electrode method,and hippocampal blood flow was measured with laser Doppler flowmetry. Liquid was continously infused at a rate of 0.08 μl/min by a microinfusion pump before 20 minutes of cerebral ischemia. Results:There was no significant diffence in NO concentration and the hippocampal blood flow among control group,physiological saline group and experimental group before and during cerebral ischemia. NO concentration of experimental group significantly decreased compared with that of control and saline group. Conclusion:Anti-TrkB antibody significantly reduced nitric oxide concentration in hippocampus after cerebral ischemia.